Fabrication of 3D CuS@ZnIn2S4 hierarchical nanocages with 2D/2D nanosheet subunits p-n heterojunctions for improved photocatalytic hydrogen evolution

Photocatalysis based on metal sulfide semiconductor is considered as an economic, safe, renewable, and clean technology. However, the availability of photocatalysts is limited by the low solar energy utilization efficiency and the fast recombination of photogenerated electron-hole pairs. Developing a hollow heterostructure photo-catalyst based on semiconductors for enhancing solar energy utilization and separation efficiency of photo-generated carriers is crucial in the photocatalytic H-2 production reaction. The as-prepared 3D hierarchical nanocages photocatalyst CuS@ZnIn2S4 with abundant and compact nanosheets 2D/2D hetero-interfaces dis -played an improved photocatalytic hydrogen evolution rate as high as 7910 mu mol h(-1) g(-1) in the absence of any cocatalyst. This is the first report of the use of CuS nanosheets-assembled hollow cubic cages to construct 3D hierarchical nanocages photocatalysts. The close distance between the two nanosheet subunits induce the strong interaction, which was advantage to the separation and transfer of charge carriers. In addition, the hollow structure can not only enhance light adsorption, but also suppress photogenerated carrier recombination. The experimental characterizations and theory calculations confirmed that the strong interaction between CuS and ZnIn2S4 2D/2D hetero-interfaces can extremely facilitate the separation of photogenerated charge carriers and accelerate the electrons transfer. The present work provides a feasible method to construct heterojunction photocatalyst for hydrogen evolution via water splitting powered.

Automated summary

Photocatalysis based on metal sulfide semiconductors is considered an economic and clean technology, but faces challenges such as low solar energy utilization and fast recombination of photo-generated carriers. This study successfully developed a hollow heterostructure photocatalyst to enhance solar energy utilization efficiency and separation efficiency of photo-generated carriers, achieving a high photocatalytic hydrogen evolution rate. The strong interaction between CuS and ZnIn2S4 in the 2D/2D hetero-interfaces was found to significantly facilitate the separation and transfer of photogenerated charge carriers.